ASTM F3208-18

5.1 This guide provides information on how to select the test soil(s) that best simulates clinical use for devices. The test soil(s) selected for the validation should be clinically relevant and simulate what the device/component will come into contact with during the clinical procedure.

5.2 This guide will help standardize the test soils used by medical device manufacturers when validating the cleaning procedures of reusable medical devices and reprocessing equipment

5.3 For devices that come into contact with blood, the simulated test soils are blood-based soils, such as those described under 7.1.1-7.1.2.

5.4 For devices that come into contact with mucus, the simulated test soils are those described under 7.1.3.

5.5 For devices that come in contact with soils of a source other than the patient (e.g., bone cement), the simulated test soils should be similar to those described in 7.2. These can be used alone or in combination with 7.1.

5.6 A combination of test soils may be used (e.g., blood with mucus) to simulate clinical soiling. For example, flexible endoscopes may come in contact with a different combination of sources of soiling (e.g., gastrointestinal (GI) tract, vasculature for biopsies) during clinical use.

5.7 Any simulated test soil(s) or formulations can be used for simulated use testing but shall be scientifically justified by the medical device manufacturer.

1.1 This guide describes methods for selecting test soils for cleaning validations based upon the characteristics of the soil, the physical characteristics of the device, and the clinical use of the device.

1.2 This guide describes the preparation and use of some test soils for the validation of cleaning instructions for reusable medical devices.

1.3 Reusable medical devices such as endoscopes, arthroscopic shavers, surgical instruments, and suction tubes are exposed to biological soils during clinical use. Preparation of these devices for reuse requires cleaning and disinfection and/or sterilization as applicable. Adequate cleaning is the first step in a process intended to prevent contaminant transfer to the next patient and medical practitioner. The soils, if inadequately removed, can interfere with disinfection and sterilization processes, as well as performance of the device. Acceptance criteria are based either on a visual assessment or quantitatively specified marker(s) endpoint(s) of the soil or both (ISO/TS 15883-5, Section 1). Endpoints after cleaning should be based upon possible interference with disinfection/sterilization, risk to the patient or health care worker from the contaminant during further handling, and endpoints for cleaning established in the scientific literature.

1.4 The test soils are designed to simulate the contaminants that medical devices are likely to come in contact with during clinical use. The test soils discussed in this guide are a mixture of constituents that simulate what is commonly found in human secretions, blood, tissue, and bone fragments/shavings as well as non-patient derived soil (e.g., bone cement, lubricants, and dyes) during clinical procedures. The test soils also simulate the physical parameters (e.g., viscosity, adhesion) of clinical material to which the medical devices will be exposed.

1.5 Exclusion: 

1.6 Test soil formulations not described in this guide may be clinically relevant and may be more appropriate for simulated-use testing depending upon the clinical use of the medical device. The burden is upon the medical device manufacturer to determine and justify scientifically the selection of test soil(s).

1.7 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.

1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.